Our brains quickly characterize everything we see as familiar or new, and scientists have been investigating this connection between vision and cognition for years. Now, research reveals that activation of neurons in a part of the primate brain called the perirhinal cortex can cause monkeys to recognize new objects as familiar and vice versa. “By increasing the firing of the perirhinal neurons, there’s a general signal sent out that says, ‘This is familiar,’” explains Paula Croxson, PhD, assistant professor of neuroscience and psychiatry at the Icahn School of Medicine at Mount Sinai. Dr. Croxson was not involved in the work. The research team saw similar results when they stimulated neurons in the anterior part of the perirhinal cortex with electricity. But when they electrically stimulated more posterior perirhinal cortex neurons, the monkeys were more likely to identify all objects as new.